Most experts agree that when it comes to writing fiction, no rules are carved in stone. A writer is free to bend, twist, smash or shred any of the golden platitudes of writing that have been handed down by the well-paid, well-respected writers we all hope to become.

Certain writing guidelines, however, are so self-evident few writers would dispute them. When these guidelines are broken, you don’t need a burning bush to tell you your writing will suffer.

1. Take yourself seriously

This is the most crucial commandment—and the most difficult to follow. Many beginning writers feel guilty about working so hard at something for which they haven’t been paid a cent. Immediate family members or friends may look on writing as a harmless little hobby, to be encouraged only when it doesn’t interfere with their own lives. Because of the cavalier attitude of others, writers may fail to prioritize writing as a necessary part of their lives, regardless of whether or not money exchanges hands.

You must emphatically demonstrate to yourself and to others that writing is a part of who you are, not just an amusing pastime. The measure of being a writer is not how much money you make, but how important writing is in your life.

2. Act like a professional

To be taken seriously as a writer, you must act like a professional writer. That means whenever you deal with other professionals in the writing business, such as agents, editors and publishers, you should act the same as you would for a job interview, and present a professional appearance. This is especially important in cover letters and manuscript preparation.

First, proofread for grammar, punctuation and spelling errors. I have heard many editors admit they sometimes reject a manuscript within the first few pages solely due to the number of grammar, punctuation and spelling mistakes. After months or even years of hard work perfecting your story, novel or screenplay, it would be a shame to have it rejected just because you didn’t bother to check your spelling or fix a sentence fragment. And don’t rely solely on spell-checking and grammar-checking computer programs—they make errors all the time. If grammar is your weakness, then find someone, either a friend or professional, who can proof the pages for you.

Second, perfect the format. The place to be creative is in your writing style, not the manuscript format. Avoid fancy fonts. They’re distracting and hard to read. Stick to standard margins. Narrow margins crowd the page and slow the story’s pace; broad margins make it appear as though you don’t have a substantial story. Don’t design your own cover. It smacks of desperation.

Third, polish the cover letter. Just tell the editors what they need to know. That includes: (a) a brief summary of the work, one to three paragraphs, and (b) anything about yourself that might be relevant to the work (if you’re submitting a police procedural novel and you’re a journalist who worked the crime beat, that’s relevant). Avoid overhyping yourself or the work by making extravagant claims: “This will earn millions of dollars!” or “The world has never seen a novel like this before!” Hyperbole makes agents and editors less eager to work with you.

3. Write your passion

Some beginning writers try to write for whatever trend is popular. But by the time you finish your manuscript, get an agent and send your work to a publisher, the trend will be on its way out. You’re more likely to produce publishable material by writing what you’re passionate about. If you love romances, then write one. If you love mysteries, then that’s the genre for you. You don’t have to write only that genre, but as you first start out, if you write what you know, you’ll have a stronger feel for the proper conventions to include as well as the cliches and stereotypes to avoid.

Ultimately, all that matters is that you care about the material and convey that passion to the reader.

4. Love the process

If you want to become a professional fiction writer, you’d better love the writing process. That doesn’t mean you don’t have doubts, fears and an aversion to your computer. It means that despite those hesitations, you still sit down and write. Even after you’ve sold your novel, finished your book-signing tour and watched Brad Pitt star in the film version, you still have to spend most of your days at a computer. That process must thrill and delight you, since all the rest of the celebrity trappings are only a small part of what you do.

5. Read—a lot

While it’s a very good idea to know your genre, the best writers don’t limit their reading to that genre. Artists need to experience other artists’ work, which can teach and inspire as well.

When I read a fascinating novel or watch an insightful movie, I can’t wait to get back to my own writing and make it better. This also works when I read a boring novel or watch a cliched movie; then I can’t wait to make sure I haven’t made similar mistakes in my work.

Reading nonfiction is also helpful to fiction writers. I’ve been so inspired by articles on scientific discoveries, political events or historical facts that I’ve later made the ideas significant parts of my fiction works. A 10-line filler in the newspaper about the auction of Napoleon Bonaparte’s penis inspired the opening chapter of my novel Earth Angel.

6. Stick to a schedule

The main difference between successful writers and wannabe writers is not talent—it’s perseverance. They finish what they start. Create a writing schedule that works for you and stick with it. Two types of scheduling work best for most writers.

1. The Gridlock Method. Fill out a weekly grid with all your responsibilities that cannot be changed—work, school, family, etc. Find two-hour blocks on at least three days of the week that you can claim for writing. Announce to your family and friends that those are your writing hours, and you are not to be disturbed during that time except for emergencies. (Be sure to define “emergencies.”)

2. The Spare-Change Method. This method is for those whose schedules are less predictable. On a calendar, write the number of pages you intend to complete per day. Regardless of how busy you are that day, commit to staying up until that number of pages is complete.

Whichever method you use, the result will be the same: You will end up with a completed manuscript.

7. Be critical of your work

Writers live with the hope that someday they will read what they’ve written and not want to tear it up. The bad news is that the better you become as a writer, the more critical you are of your writing. The more you know about writing, the less you can tolerate bad writing (your own or others’). The good news is this critical ability will make you better. You will learn to reject the predictable and strive for invigorating style, plotting and characterization. Stop worrying that you’ll never be a good enough writer, and embrace the inner critic.

8. Develop thick skin

As a beginning writer, I dreamed of the day when I would never have to face another rejection. Forty published books and 12 sold screenplays later, not a day goes by when something I’ve written or proposed to be written isn’t rejected by someone. Usually, some publisher or producer buys what I’ve written, but not always. I still have a few unsold novels stashed in my garage, rejected stories and poems in my filing cabinet, script treatments on my desk.

Rejection still stings. But it doesn’t hurt as long as it used to because I have so many projects to pursue. I no longer mope around and curse the short-sightedness of a universe that fails to recognize my genius. I just work on the next project. And if the same manuscript keeps getting rejected for the same reason, I re-evaluate the work and maybe rewrite it.

9. Trust your editors

First, I’m going to broadly define editors as not only professional editors at publishing houses but also writing teachers and writing workshop members who read and offer editorial suggestions. Most editors aren’t frustrated writers—some are accomplished writers publishing more than you. In general, they have your best interests at heart. That doesn’t mean you won’t have disagreements with their suggestions. You most certainly will. You may even be right sometimes. But you will miss out on some very helpful suggestions if you refuse to listen.

The goal of most editors is to help you best realize the story you want to write. Because they come at it with fresh perspectives, they may be able to see flaws that you can’t because you’re too close to the work.

My typical first reaction to editorial suggestions is this: “What an idiot! You understand nothing of what I’m trying to say.” An hour later I think, “Maybe that’s not a completely stupid idea.” After I incorporate the idea I think, “I’m a genius to have thought of this change.” Point is, I have learned to carefully consider each suggestion. Sometimes I reject them, but many times those suggestions have significantly improved my work.

10. There are no certainties

William Goldman said it about Hollywood in his excellent primer for screenwriters, Adventures in the Screen Trade (Warner Books), but it applies equally to all writing. No one knows for sure what’s going to sell and what isn’t. If an agent from a big agency or an editor from a major publisher rejects your book saying that no one’s interested in that type of story anymore, that doesn’t necessarily mean anything. Think of all the “knowledgeable” studio execs who rejected Star Wars or big-shot editors who turned down The Godfather.

You must develop your own instincts about writing and have faith in them even when no one else does. That doesn’t mean you will be inflexible to suggestions, it just means you will feel confident in whatever decisions you make.